By the end of the Middle Ages, Spain did not exist as a country. The Iberian Peninsula was then a conglomerate of independent kingdoms – Castille, Aragon, Navarra, Portugal and the Moorish (arab) kingdom of Granada
King Juan II of Castille (1405-1454) lost his first wife, Maria of Aragon, in 1445The couple had one adult son, Enrique (1425-1474). Since early childhood Enrique had been of poor health and melancholic. He had married princess Blanca of Navarra, but seven years after their marriage, this couple still had no heir. It was public voice that the marriage had not been consummated and that the prince was probably impotent.
So the king Juan conceived the idea of a second marriage that might secure his dynasty's lineage. Alvaro de Luna, the king's constable and confident, proposed the name of Isabel, a cousin of king Afonso V of Portugal. The marriage was negotiated and Juan II of Castille married Isabel of Portugal in 22 July 1447. The bride was three years younger than her step-son.Four years later, on 22 April 1451, Isabel gave birth to a daughter, which was called after her Isabella. She had a difficult labor and suffered from a post-labor depression. She suffered from long periods of "profunda tristeza". On 15 November 1453 she gave birth to a son, Alfonso. For the rest of her life Isabel became a nervous wreck close to insanity.
The crown prince, Enrique, realized then that he had a problem of succession. His first step was to seek divorce of his wife.
He alleged that it was Blanca's fault that they never reached "carnal copulation" and that he was not similarly incapacitated with other women. Blanca added that she had never offered the slightest impediment to the marital act. She was then subject to the humiliation of being physically investigated by two old ladies to verify that she was a virgin. At the same time a priest was sent to inquire about the sexual habits of the Crown Prince in the brothels of Segovia. Apparently it was not difficult to bribe some prostitutes to testify on Enrique's sexual prowess.
Juan II passed away in July 1454 and the crown prince ascended to the throne of Castille as Enrique IV.
The new king then married the cousin of his step-mother. Joana of Portugal, sister of king Afonso V, is described as "gay and coquettish". With her Enrique continued his desperate efforts. But his second wife remained intact too.
A German doctor, Hieronymus Münzer, has examined the king. I will spare the reader from the details of his report, according to which Enrique was physically unable to have an erection.
Meanwhile Enrique had sent his step-mother and her to little children, Isabella and Alfonso, to the castle of Arévalo, where she lived in great seclusion and depression, a very frugal life.
In 1452, her daughter, Isabella, was taken from her and sent to a convent in Avila to continue her education. (This is the Isabella, that was to become queen of Castille, and soon we will se how).
Meanwhile, at the court, what seemed to be impossible became true: Joana, the queen became pregnant. Some say it was a miracle, others that it was the result of some sort of artificial insemination that the couple had tried. She gave birth to a daughter, named Juana, after the mother. Soon the child was known at the court and elsewhere as the "Beltraneja", after Don Beltrán de la Cueva, a favorite of both the King and the Queen, who the gossip said was the real father of Juana.
The favors bestowed by the king to his new favorite, Beltrán de la Cueva, raised the jealousy of his former favorite, Juan Pacheco, Marquis of Villana.
In 1465, he and other nobles of the court of Castille started a civil war, declaring the eleven-year-old second son of Juan II from his second wife, the mad Isabel de Portugal, as King of Castille.. In August 1467 a great battle was fought at Olmedo. Enrique was not to be found, while his wife, Joana, fled with "La Beltraneja" to Segovia.
But in July 1468, fourteen-years-old Alfonso died from a sudden illness.
In September of the same year Enrique and his young sister Isabela met for reconciliation. Enrique was satisfied from the homage that he received from the nobles, and recognized Isabella as heir to the throne.
Thereby he disinherited La Beltraneja, whose mother, Joana of Portugal, Queen of Castille, angrily left her husband, took a lover and gave birth to two more children.
When, in 1469, the young Isabella was threatened with confinement by her half-brother Enrique IV, she pretended to go and visit her mother in Arévalo, but instead traveled to Valladolid, where she secretly married Crown Prince Ferdinand of Aragon.
When Enrique IV died in 1474, young Isabella was crowned Queen Isabella I of Castille.
This was against the interests of King Afonso V of Portugal, who had the intention of marrying the Beltraneja and inherit with her the crown of Castille.
In the civil war that followed, Gedaliah Ben David Yahia Negro, Afonso's physician and astrologer, accompanied the king to the battle field. From there he reported in Hebrew to his colleague and fellow Jew, Isaac Abravanel, on the progress of the troops.
"…the castle [of Benavente]" – he wrote – "is ready to surrender to [our] King, against his own will, because the men of the castle had mocked the [former] King [of Castille, Enrico IV], by saying that he was a sodomite and his wife an adulteress and [her daughter] a bastard and they had hanged a pair of horns in a high place…"
In 1476 Afonso V lost the last battle at Toro and the "Beltraneja" lost definitively the throne of Castille.
In 1479, on the death of his father King Juan II of Aragon, Ferdinand, who was already King of Sicily, inherited the throne of Aragon, as Ferdinand II. With his wife Isabella I he assumed the joint rule of Castille and Leon, as Ferdinand V.
The royal couple, known as the Catholic kings, set out with energetic determination to complete the unification, and Granada fell to them at last in 1492. The new unified Kingdom of Spain was born.
In the same year Ferdinand and Isabella took the fateful step of expelling from their kingdoms all Jews who refused to accept Christianity.
© Inacio Steinhardt, 2003
 Gedaliah Negro was a physician and a astrologer in the court of King Afonso V of Portugal. Isaac Abravanel was the kings's adviser and financier.
 Thanks to the long trip made by Hieronymus Münzer in Spain in Portugal we have the only description of the Great Synagogue of Lisbon, before the forced conversion of the Jews of Portugal, and before it was destroyed, already as a church, by the 1755 earthquake.
 An old custom in Spain and Portugal, to hang a large pair of horns, made of wood or cloth, to show that a man is a cuckold .
FOR FURTHER READING:
Isabella of Castille: The First Renaissance Queen
L'élevage sous les rois catholiques dans le royaume de Castille (1454-1516) (Publications de la Casa de Velázquez)
Isabel Of Spain: Catholic Queen
Isabel The Queen: Life And Times (The Middle Ages Series)
Isabel la Católica, Queen of Castile: Critical Essays
Isabel, Ferdinand and Fifteenth-Century Spain (Rulers and Their Times)
The Sovereigns and the Admiral: A Biography of Isabel,Ferdinand and Columbus
The Book of Privileges Issued to Christopher Columbus by King Fernando and Queen Isabel: 1492-1502.: An article from: Renaissance Quarterly
A Queen of Queens & the Making of Spain Isabel of Castile and the making of the Spanish nation, 1451-1504, Isabel LA Catolica: Una Reina Vencedora, Una Mujer Derrotada (Coleccion Historia (Ediciones Temas De Hoy).)
Isabel, mujer y reina (Colección literaria)
Isabel la Católica: Estudio crítico de su vida y su reinado (Biblioteca de autores cristianos)
Testamento de Isabel la Católica y Acta matrimonial: Cuyos originales se encuentran en el Archivo General de Simancas
Ferdinand and Isabella Testamento de Isabel la Católica y Acta matrimonial (Tabula Americae)
Testamento de Isabel la Católica y Acta matrimonial (Tabula Americae)
Annals of the Emperor Charles V,
Isabel I de Castilla: La Reina Católica, 1451-1504 (Vidas privadas)
History of the reign of Ferdinand and Isabella, the Catholic